1. Field of the Present Disclosure
The present disclosure relates to a film deposition method and a film deposition apparatus which are adapted to deposit a film on a substrate by supplying at least two kinds of mutually reactive gases to the substrate.
2. Description of the Related Art
Along with further miniaturization of circuit patterns in semiconductor devices, various films that constitute the semiconductor devices are demanded to be thinner and more uniform. As a film deposition method capable of responding such demand, a so-called Molecular Layer Deposition (MLD) method (to be also referred to as an Atomic Layer Deposition (ALD) method) has been drawing attention (for example, Patent Document 1). In such a film deposition method, a first reaction gas is adsorbed on a surface of a substrate by supplying the first reaction gas to the substrate, and then a second reaction gas is supplied to the substrate so that the first reaction gas adsorbed on the surface of the substrate reacts with the second reaction gas and a film composed of a reaction product of the gases is deposited on the substrate. A turntable type is known as a film deposition apparatus for performing the MLD method.
For example, an MLD apparatus proposed by the inventors includes: a rotation table on which a substrate is placed; a first reaction gas supply unit for supplying a first reaction gas to the turntable; a second reaction gas supply unit for supplying a second reaction gas to the turntable; and a separation area that is provided between the first reaction gas supply unit and the second reaction gas supply unit and that separates the first reaction gas and the second reaction gas. The separation area is provided with an area to which the first reaction gas is supplied, a ceiling plane lower than an area to which the second reaction gas is supplied, and a separation gas supply unit for supplying a separation gas (Patent document 2).
In such a MLD apparatus, the turntable rotates so that the first reaction gas is adsorbed on a surface of the substrate on the turntable. Then, the first reaction gas adsorbed on the surface of the substrate reacts with the second reaction gas so that a reaction product is generated on the surface of the substrate and a film of the reaction product is deposited on the surface of the substrate. Especially significant, the first reaction gas and the second reaction gas are sufficiently separated by the separation area. Thus, throughput can be improved by increasing the rotation speed of the turntable.
However, in the conventional technique, it is difficult to deposit a thin film having superior film-thickness distribution and superior film quality while maintaining the film deposition speed.
Patent Document 1: Japanese Laid-Open Patent Publication No. 2001-254181
Patent Document 2: Japanese Patent No. 4661990 (corresponding to Japanese Laid-Open Patent Publication No. 2010-263245)